Skip to Main content Skip to Navigation
Theses

Modélisation du comportement élasto-viscoplastique des aciers multiphasés pour la simulation de leur mise en forme

Abstract : Due to the restriction imposed by EU on the CO2 emission performance standards for the automobile sector, the automobile manufacturers need to produce lighter vehicles, mostly by reducing the thickness of the automobile parts. As a consequence, the steel companies have to propose new steels capable to ensure similar or higher passenger safety. Increasing the mechanical properties is not a viable solution as that can decrease the metal formability. A balance between the both can be obtained by microstructure optimization. This can be achieved through a combination of good properties of different phases, as for example in new generation multiphase steels. The microstructure optimization can require a large number of experimental trials. Numerical simulation is an efficient tool to diminish the time and the costs of product conception by reducing the number of experimental campaigns. This present research aims at the development of a numerical solution to model the elastic-viscoplastic behavior of multiphase steels grades during 3D finite element simulations of metal forming processes with Abaqus software. A phenomenological physics-based constitutive model is proposed for the elastic-viscoplastic behavior of the constitutive phases. This original tensorial constitutive law (incremental formulation) is verified by the experimental data and other constitutive laws proposed in the literature. The macroscopic behavior of the multiphase steel is obtained by using a self-consistent approach written specifically for heterogeneous elastic-viscoplastic materials. In addition, a new micromechanical approach is considered to capture microstructure size effects (grain size, particle size, etc.) and is validated on previously published experimental results. The numerical tool developed in the current research is applied on the tensile and V-bending simulations to evaluate its ability to predict accurately physical phenomena (such as striction, strain-rate effects on localization and Bauschinger effect) in a composite elastic-viscoplastic structure.
Complete list of metadatas

Cited literature [93 references]  Display  Hide  Download

https://pastel.archives-ouvertes.fr/pastel-00668551
Contributor : Jean-Marc Pipard <>
Submitted on : Thursday, February 9, 2012 - 11:04:28 PM
Last modification on : Friday, July 17, 2020 - 2:57:08 PM
Long-term archiving on: : Thursday, May 10, 2012 - 3:00:16 AM

Identifiers

  • HAL Id : pastel-00668551, version 1

Citation

Jean-Marc Pipard. Modélisation du comportement élasto-viscoplastique des aciers multiphasés pour la simulation de leur mise en forme. Mécanique des matériaux [physics.class-ph]. Arts et Métiers ParisTech, 2012. Français. ⟨NNT : 2012ENAM0001⟩. ⟨pastel-00668551⟩

Share

Metrics

Record views

1277

Files downloads

8884